Nowroozzadeh1 suggested that the protective effect of allergy on the development of age-related macular degeneration (AMD)2 may be due to antiallergic drugs by modulating the immune response. In our statistical analysis, we already had adjusted for corticosteroid use to exclude a drug-related effect. In addition to corticosteroids, only 18 of 1878 persons (0.96%) in the Cologne cohort used other antiallergic drugs. Therefore, a potential effect of these drugs is negligible. Overall, it would be surprising if common antiallergic drugs had such a highly protective effect as seen in our study with allergy.

Nowroozzadeh also suggested to differentiate possible drug effects in patients with neovascular AMD and geographic atrophy. In the study, we had included an analysis for late AMD, which comprised mainly patients with neovascular AMD. Additionally, we had carried out a subgroup analysis for patients with geographic atrophy. In both groups, allergy was a similarly strong protective factor.